SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3029821173ba35986b0575b3100f0de5c962db57454fd8288864c043c7762f3b' 
  AND token = 'iwaB4xZFCl7Fkp/V/BiPjZzO0SgKq02QS19sEBJR//M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}